Communication buses are many and varied, as exemplified in computer backplanes, board buses, buses inside integrated circuits, bus standards, local area networks, wide area networks, and ad hoc and proprietary buses connecting devices. One bus in widespread use is the CAN (controller area network) bus, originally developed for vehicles. The CAN bus is a multi-master broadcast serial bus, which may be implemented using balanced pair signals in twisted-pair wires, optionally in shielded cables. Other buses may employ differential line drivers and differential receivers. Many buses support two states, “1” and “0”, or three states, “1”, “0” and “Z” or high impedance. Yet, components for many of these buses may be more expensive than desired, have complex protocols, or may not function well in harsh environments such as automotive. There is a need in the art for a solution which overcomes the drawbacks described above, and/or has features suited for a specific environment.